Prior art is replete with anchor devices to be used by ricj ckimbers to secure a hold within the crack of a rock and allow removal after use. A search of the prior art did not disclose any patents that read directly on the claims of the instant invention, however, the following U.S. patents are considered related.
______________________________________ U.S. Pat. No. Inventor Date Issued ______________________________________ 4,184,657 Jardine Jan. 22, 1980 4,074,880 Simond Feb. 21, 1978 4,069,991 Sanders et al Jan. 24, 1978 3,903,785 Pepper, Jr Sept. 9, 1975 3,877,679 Lowe Apr. 15, 1975 ______________________________________
Jardine teaches a climbing aid having many of the same elements as the instant invention, such as a support bar having a longitudinal slot and an attachment point near the end. A pair of spring loaded opposed cams supported on a spindle and an operating bar attached to the cams provide the locking arrangement. A pair of wires, with one section rigid, are attached to an operating bar supplying the adjustment and retracting features allowing the climbing aid to be placed into a fissure or crack. It will be noted that this type of device utilizes only a single support bar with a square end and the spindle is supported only in the middle structurally through the bar near the opposite end. No provision is made to hold the operating bar into the longitudinal slot in any direction with the flexible wires being the containment, however, not lending any lateral support at all. The shape of the cams is important to consider as the radial section does not extend beyond a 90 degree angle when fully extended. With this prior art in mind, it is the purpose of the instant invention to improve this type of device in strength and functional operation.
Simond teaches a plurality of wedges that may be used in concert, each having its own attaching holes for ropes to pass therethrough.
Sanders et al similarly disclose a chock having a unitary body with a pair of holes on one side with mating slots on the other. Their invention has three sides and beveled end faces to allow camming action on various sides and also the ends.
Pepper, Jr. employs a three piece mechanism that interlocks outer parts and utilizes a wedge shaped expander. When tension is applied to an inner member the two coacting outer parts are forced apart and a loop of cable transmits an axial load from the wedge, as all the parts are attached together.
Lowe teaches a chock that utilizes one main body member in wedge shape with an orientation assembly pivotally attached between a pair of spaced surfaces. The two members are spring loaded together forcing the pair apart into the crack or fissure. The main body member is provided with an arcuate cam surface arranged to present a constant intercepting angle with respect to the surface upon which it abuts. The arrangement, therefore, functions as a levering cam apparatus when placed within a crack or crevice in a rock surface.